Mobile communication terminal

ABSTRACT

A mobile phone unit is provided in which a characteristic of an antenna is improved and SAR is reduced without lowering an antenna gain during communication. An antenna  26  (electrical length λ/4), an antenna connection conductive member  22  (electrical length λ/4) that is a circuit board connected to the antenna  26 , an opposite side conductive member  42  that is a circuit board opposed to the antenna connection conductive member  22 , and an electric connection portion  24  that electrically connects an edge portion  222 , which is on the opposite side to the antenna  26 , of the antenna connection conductive member  22  and an opposite side edge portion  422 , which is opposed to the edge portion  222 , of the opposite side conductive member  42  (electrical length λ/4) are included. A gain on the opposite side to an LCD side casing  4  becomes large when seen from the antenna  26 , and the electric currents are counteracted to be small and consequently a gain becomes small on the side of the LCD side casing  4.

TECHNICAL FIELD

The present invention relates to a mobile communication terminal such asa mobile phone unit, and particularly to a technology of reducing SAR(Specific Absorption Rate) in the mobile communication terminal.

BACKGROUND ART

At present, wireless communication, for example, a telephone call usinga mobile wireless communication terminal such as a mobile phone unit andthe like is performed. An electromagnetic wave is radiated from anantenna of a mobile phone unit when making a telephone call. A part ofthe electromagnetic wave radiated is absorbed by the user using themobile phone unit. It is desirable that the electromagnetic waveabsorbed into the human body is low. Here, as one of the indices thatshow the amount of the absorption of the electromagnetic wave into thehuman body, there is the SAR that is the absorption rate of theelectromagnetic wave energy applied to a specific portion of the humanbody. Hence, it is desirable that the SAR be reduced. However, if theelectromagnetic wave radiated from an antenna is reduced just becausethe reduction of the SAR is desired, an antenna gain during a telephonecall is dropped to cause a disadvantage to the telephone call.

Thus, it is preferable not to lower the antenna gain during a telephonecall while improving the characteristic of the antenna and reducing theSAR. Hereupon, one in which the characteristic of the antenna isimproved to control the interference between the antennas (refer toPublished Japanese Patent Application No. 2003-163521), and one in whichthe reduction of the influence of the casing to the antenna (refer toPublished Japanese Patent Application No. H9-270728) are proposed.

However, there is no such thing as the characteristic of the antenna isimproved and the antenna gain during a telephone call is held whilereducing the SAR.

Therefore, the present invention aims not to lower an antenna gainduring a telephone call while reducing the SAR by improving thecharacteristic of the antenna.

DISCLOSURE OF THE INVENTION

The first aspect of the present invention is a mobile communicationterminal including: an antenna, an antenna connection conductive memberconnected to the antenna, an opposite side conductive member opposed tothe antenna connection conductive member, and an electric connectionmember which electrically connects an edge portion, which is on theopposite side to the antenna, of the antenna connection conductivemember and an opposite side edge portion, which is opposed to a vicinityof the edge portion, of the opposite side conductive member.

The second aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, whereinthe electric connection member connects a ground potential portion ofthe antenna connection conductive member and a ground potential portionof the opposite side conductive member.

The third aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, furtherincluding a casing which accommodates the opposite side conductivemember, and the casing has a voice output means which outputs the voiceon the side opposite to the antenna connection conductive member whenseen from the opposite side conductive member.

The fourth aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, whereinthe electric connection member performs

(1) no operation of connecting the edge portion and the opposite sideedge portion, while waiting for communication, and

(2) operation of connecting the edge portion and the opposite side edgeportion during communication.

The fifth aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, whereinthe electric connection member performs

(1) operation of connecting the edge portion and the opposite side edgeportion, and further operation of electrically connecting an edgevicinity portion in the vicinity of the edge portion of the antennaconnection conductive member and a opposite side edge vicinity portionof the opposite side conductive member, which is opposed to the edgevicinity portion, while waiting for communication, and

(2) operation of connecting the edge portion and the opposite side edgeportion and no operation of connecting the edge vicinity portion and theopposite side edge vicinity portion during communication.

The sixth aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, whereinthe total electrical length of the antenna connection conductive memberand the opposite side conductive member is half the wavelength of aradio wave used for communication.

The seventh aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, whereinthe total electrical length of the antenna connection conductive memberand the opposite side conductive member is quarter the wavelength of aradio wave used for communication.

The eighth aspect of the present invention is a mobile communicationterminal according to the first aspect of the present invention, whereina frequency adjusting member is attached to the electric connectionmember.

The ninth aspect of the present invention is a mobile communicationterminal according to the eighth aspect of the present invention,wherein the frequency adjusting member is formed of at least one ofcircuit components of a resistor, a capacitor and a coil.

The tenth aspect of the present invention is a mobile communicationterminal including: radio wave radiation means, radio wave radiationconnection conductive means connected to the radio wave radiation means,opposite side conductive means opposed to the radio wave radiationconnection conductive means, and electric connection means whichelectrically connects a vicinity of the edge portion on the oppositeside to the radio wave radiation means in the radio wave radiationconnecting conductive means and a vicinity of the opposite side edgeportion of the opposite side conductive member, which is opposed to thevicinity of the edge portion.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B show an example of a mobile phone unit (mobilecommunication terminal) according to a first embodiment of the presentinvention, in which FIG. 1A is a plan view and FIG. 1B is a front view;

FIG. 2 is a plan view of an example of a mobile phone unit, in which anLCD side casing is rotated around a hinge as an axis;

FIG. 3 is a front sectional view of an example of a mobile phone unitaccording to the first embodiment of the present invention;

FIG. 4 is a characteristic curve showing an example of electric currentdistribution of a mobile phone unit according to the first embodiment ofthe present invention;

FIG. 5 is an explanatory view that defines directions regarding a mobilephone unit according to the first embodiment of the present invention;

FIG. 6 is a characteristic diagram showing an example of the antennacharacteristic assuming that there is no electric connection portion;

FIG. 7 is a characteristic diagram showing an example of the antennacharacteristic according to the first embodiment of the presentinvention;

FIGS. 8A and 8B are sectional views of an example of a mobile phone unitaccording to a second embodiment of the present invention, in which FIG.8A shows the time of waiting for communication (not connected) and FIG.8B shows the time of communication (connected);

FIGS. 9A and 9B are sectional views of an example of a mobile phone unitaccording to a third embodiment of the present invention, in which FIG.9A shows the time of communication (one connected) and FIG. 9B shows thetime of waiting for communication (both connected);

FIGS. 10A and 10B show an example of a mobile phone unit (mobilecommunication terminal) according to a fourth embodiment of the presentinvention, in which FIG. 10A shows a front view and FIG. 10B shows aside sectional view;

FIGS. 11A to 11C show an example of a mobile phone unit (mobilecommunication terminal) according to a fifth embodiment of the presentinvention, in which FIG. 11A is a plan view, FIG. 11B is a front viewand FIG. 11C is a front sectional view;

FIG. 12 is a front sectional view of a mobile phone unit according to asixth embodiment of the present invention;

FIGS. 13A to 13E are constitutional diagrams showing connection examplesof a frequency adjusting member according to the sixth embodiment of thepresent invention;

FIGS. 14A and 14B are frequency characteristic diagrams according to thesixth embodiment of the present invention, in which the characteristic.without a frequency adjusting member (FIG. 14A) and the characteristicwith a frequency adjusting member (FIG. 14B) are compared;

FIG. 15 is a front sectional view of an example of a mobile phone unitaccording to a seventh embodiment of the present invention; and

FIG. 16 is a constitutional diagram showing a connection example of afrequency adjusting member according to the seventh embodiment of thepresent invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be explained withreferring to the drawings.

FIRST EMBODIMENT

FIGS. 1A and 1B show a mobile phone unit (mobile communication terminal)1 according to the first embodiment of the present invention, in whichFIG. 1A is a plan view and FIG. 1B is a front view.

The mobile phone unit 1 includes a key button side casing 2, an LCD sidecasing 4 and a hinge 6. The key button side casing 2 and the LCD sidecasings 4 are opposed to each other with a small space in between andare joined by the hinge 6. The hinge 6 is disposed in the space betweenthe key button side casing 2 and the LCD side casing 4 on the edges ofthe key button side casing 2 and LCD side casing 4. The LCD side casing4 is capable of rotating around the hinge 6 as an axis. The direction ofthe axis of the rotation is vertical to the surface of the key buttonside casing 2 opposed to the LCD side casing 4.

The LCD side casing 4 includes a receiver (voice output means) 4 a, amicrophone 4 b and an LCD 4 c on the opposite side surface to thesurface opposed to the key button side casing 2. The receiver (voiceoutput means) 4 a outputs voice. It is provided mainly for a user of themobile phone unit 1 to hear the voice of the other end of the line. Theuser of the mobile phone unit 1 can hear the voice of the other end ofthe line by applying the receiver 4 a to an ear. The microphone 4 b isprovided to convert the voice of the user of the mobile phone unit 1into an electric signal. The LCD 4 c is a liquid crystal display todisplay the message and so on.

FIG. 2 is a plan view of the mobile phone unit 1, when the LCD sidecasing 4 is rotated around the hinge 6 as an axis. When the LCD sidecasing 4 is rotated around the hinge 6 as an axis, the key buttons 2 a(ten-key buttons and the like) provided on the key button side casing 2can be shown. A telephone call may be made in the state shown in FIG. 2.However, the mobile phone unit 1 can wait for phone calls and make thephone calls in the state shown in FIG. 1. Therefore, in the followingdescription the explanation will be made assuming that phone calls arewaited and performed in the state shown in FIG. 1.

FIG. 3 is a front sectional view of the mobile phone unit 1 according tothe first embodiment of the present invention.

The key button side casing accommodates an antenna connection conductivemember 22, an electric connection portion 24, an antenna 26 and abattery 28.

The antenna connection conductive member 22 is a circuit board on whichvarious electric circuits are mounted. The antenna 26 that iselectromagnetic wave radiation means is connected to the antennaconnection conductive member 22. Hereupon, if the wave-length of a radiowave that the mobile phone unit 1 uses for the communication (telephonecall) is λ, λ/4 is the electrical length of the antenna connectionconductive member 22, that is, the electrical length from a point wherethe antenna connection conductive member 22 and the antenna 26 areconnected to an edge portion 222 described later on.

The electric connection portion 24 is a member by which a groundpotential portion in the vicinity of the edge portion 222 of the antennaconnection conductive member 22 and a ground potential portion in thevicinity of an opposite side edge portion 422 of the opposite sideconductive member 42 are electrically connected through a connectionpattern 44. As the electric connection portion 24, a coil spring, agasket and various other members that are usually used for the electricconnection can be used. Note that the edge portion 222 is an edgeportion, which is on the opposite side to the antenna, of the antennaconnection conductive member 22. Further, with respect to the antennaconnection conductive member 22 and the opposite side conductive member42, a circuit between both the circuit boards is electrically connectedto be capable of performing signal communication by wiring means 61 suchas a flexible circuit board not illustrated. The ground potentialportions of both the circuit boards are also connected using the wiringmeans 61.

The antenna 26 is an antenna to perform communication. The electricallength of the antenna 26 is λ/4. Further, a feed point of the antenna 26is in the vicinity of the antenna 26.

The battery 28 is a power source of the mobile phone unit 1.

The LCD side casing 4 accommodates the opposite side conductive member42.

The opposite side conductive member 42 is a circuit board on whichvarious electric circuits are mounted. The opposite side conductivemember 42 is opposed to the antenna connection conductive member 22. Theelectrical length of the opposite side conductive member 42, that is,the electrical length to the opposite side edge portion 422 from an edgeof the opposite side conductive member 42, which is on the opposite sideto the edge portion of the other side 422, is λ/4. The opposite sideedge portion 422 of the opposite side conductive member 42 is opposed tothe edge portion 222 of the antenna connection conductive member 22. Aconnection pattern 44 is connected to the opposite side edge portion422. The connection pattern 44 passes through the hinge 6 and isconnected to the electric connection portion 24. Further, the receiver 4a is disposed in the vicinity of the edge of the opposite sideconductive member 42 on the opposite side to the opposite side edgeportion 422.

Next, the operation of the first embodiment is explained.

When communication is performed using the mobile phone unit 1, power issupplied to the antenna 26. The feed point of the antenna 26 is in thevicinity of the antenna 26. Further, the electrical length of theantenna 26 and antenna connection conductive member 22 is λ/4.Therefore, the electric current distribution of the antenna 26 andantenna connection conductive member 22 becomes similar to a λ/2wavelength dipole antenna (center feeding type) as shown in FIG. 4. Inother words, the electric current becomes maximum in the vicinity of theantenna 26 (the electrical length λ/4). Therefore, a gain on theopposite side (back side) to the LCD side casing 4 becomes large whenseeing from the antenna 26. Further, the electric current becomesminimum in the vicinity of the electric connection portion 24 (theelectrical length λ/2). Furthermore, the electrical length of theopposite side conductive member 42 is λ/4. Therefore, the electriccurrent in the vicinity of the receiver 4 a (the electrical length 3λ/4)is approximately the same as that in the vicinity of the antenna 26 (theelectrical length λ/4) with reverse polarity. Accordingly, on the sideof the LCD side casing 4 (front side) when seeing from the antenna 26,the electric current counteracts each other to be small and a gainbecomes small.

Here, directions are defined as shown in FIG. 5. FIG. 6 is a diagramshowing a characteristic of an antenna, when assumed that the electricconnection portion 24 is not provided. The radio wave is almostsimilarly radiated to the front side and the back side. There is thereceiver 4 a on the front side, and an ear of the user is brought tocontact with the receiver 4 a. Therefore, the user is exposed to theradio wave of the same level as the back side. FIG. 7 is a diagramshowing the antenna characteristic according to the first embodiment ofthe present invention. The radio wave radiated to the front side is lessthan that radiated to the back side. Therefore, the user is exposed tothe radio wave of the lower level than that of the back side. This leadsto the SAR reduction. Further, the radio wave radiated to the back sideis almost equal to that of FIG. 6. Therefore, the antenna gain duringcommunication is not considerably reduced.

According to the first embodiment, when seeing from the antenna 26, theelectric currents counteract each other to be small, and the gainbecomes small on the side of the LCD side casing 4 (front side).Therefore, the SAR is made to be reduced. Further, when seeing from theantenna 26, a gain on the opposite side to the LCD side casing 4 (backside) becomes large. Therefore, the antenna gain during communication isnot considerably reduced.

SECOND EMBODIMENT

In the second embodiment, the connection state of the electricconnection portion 24 is changed between the time of waiting forcommunication (not connected) and the time of communication (connected),which is different from the first embodiment.

An outer appearance of a mobile phone unit 1 according to the secondembodiment is the same as that shown in FIGS. 1 and 2.

FIGS. 8A and 8B are sectional views of the mobile phone unit 1 accordingto the second embodiment of the present invention, in which FIG. 8Ashows the time of waiting for communication (not connected) and FIG. 8Bshows the time of communication (connected).

As shown in FIG. 8A, the antenna connection conductive member 22 and theopposite side conductive member 42 are not connected through theelectric connection portion 24 in the time waiting for the communication(telephone call). On the other hand, as shown in FIG. 8B, the antennaconnection conductive member 22 and the opposite side conductive member42 are connected through the electric connection portion 24 in the timeof communication. However, the two conductive members 22, 42 areconnected through wiring means (not illustrated in FIG. 8) such that thesignal communication can constantly be performed. Note that the otherportions are the same as those of the first embodiment, and the samenumerals are given to the same portions and the explanation thereof isomitted.

Next, the operation of the second embodiment is explained. When themobile phone unit 1 is waiting for communication (telephone call) (referto FIG. 8B), the feed point of the antenna 26 is in the vicinity of theantenna 26. Further, the electrical length of the antenna 26 and theantenna connection conductive member 22 is λ/4. Therefore, the electriccurrent distribution of the antenna 26 and the antenna connectionconductive member 22 becomes similar to a λ/2 wavelength dipole antenna(center feed type). In other words, the electric current becomes maximumin the vicinity of the antenna 26 (the electrical length λ/4).Therefore, when seeing from the antenna 26, a gain on the opposite sideto the LCD side casing 4 (back side) becomes large. Further, theelectric current becomes minimum in the vicinity of the electricconnection portion 24 (the electrical length λ/2).

Hereupon, the antenna connection conductive member 22 and the oppositeside conductive member 42 are not connected. Therefore, the antennaconnection conductive member 22 and the opposite side conductive member42 cause the capacity coupling. Accordingly, the electric currentbecomes minimum in the vicinity of the opposite side edge portion 422 ofthe opposite side conductive member 42 and the electric current becomesmaximum in the vicinity of the receiver 4 a. Hence, a gain becomes alsolarge on the side of the LCD side casing 4 (front side) when seeing fromthe antenna 26.

Therefore, almost the same antenna characteristic is shown on the frontside and on the back side when waiting for the communication (telephonecall). Hence, if the radio wave comes (radiates) either from the frontside or from the back side, the reception (transmission) can beperformed favorably, which is suitable to wait for the communication(telephone call).

On the other hand, the operation when performing the communication usingthe mobile phone unit 1 is similar to that of the first embodiment. Forexample, in FIGS. 8A and 8B, L1 (whole length of the key button sidecasing 2) is 105 mm and L2 (the distance from the end surface (theopposite side to the antenna 26) of the key button side casing 2 to theelectric connection portion 24) is 45 mm and the radio wave of the 800MHz band is used for the communication (telephone call). Thecharacteristics of the antenna are as follows. TABLE 1 During Front sideBack side communication Without the electric −5 dBi −5 dBi −15 dBiconnection portion 24 With the electric −8 dBi −5 dBi −12 dBi portion 24

According to the above table, without the electric connection portion 24(refer to FIG. 8A), almost the same antenna characteristic is shown onthe front side and on the back side to be suitable for waiting for thecommunication (telephone call). With the electric connection portion 24(refer to FIG. 8B), the antenna characteristic during communication isfavorable, which is suitable for the time of communication.

According to the second embodiment, when waiting for the communication(telephone call), the electric connection portion 24 is not provided andthe antenna connection conductive member 22 and the opposite sideconductive member 42 are not connected, so that almost the same antennacharacteristic is shown on the front side and on the back side.Therefore, it is suitable to wait for communication (telephone call).Furthermore, the same effectiveness as the first embodiment is obtainedduring communication.

In addition, whether the electric connection portion 24 is connected ornot is changed between the time of waiting for communication and thetime of the communication in the above explanation, however, theswitching may be performed by the opening and closing (the changebetween the states of FIGS. 1 and 2) of the two casings 2 and 4.

THIRD EMBODIMENT

In the third embodiment, the electric connection portions 24 a, 24 b areprovided instead of the electric connection portion 24 and theconnection states thereof are changed between the time of waiting forcommunication (both connected) and the time of communication (oneconnected), which is different from the first embodiment.

An outer appearance of a mobile phone unit 1 according to the thirdembodiment is the same as that shown in FIGS. 1 and 2.

FIGS. 9A and 9B are sectional views of the mobile phone unit 1 accordingto the third embodiment of the present invention, in which FIG. 9A showsthe time of communication (one connected) and FIG. 9B shows the time ofwaiting for communication (both connected).

The opposite side edge portion 422 of the opposite side conductivemember 42 is opposed to the edge portion 222 of the antenna connectionconductive member 22. A connection pattern 44 a is connected to theopposite side edge portion 422. The connection pattern 44 a passesthrough the hinge 6 and is connected to the electric connection portion24 a. The electric connection portion 24 a electrically connects theedge portion 222 of the antenna connection conductive member 22 to theopposite side edge portion 422 of the opposite side conductive member 42through the connection pattern 44 a.

An opposite side edge vicinity portion 424 of the opposite sideconductive member 42 is in the vicinity of the opposite side edgeportion 422 of the opposite side conductive member 42. An edge vicinityportion 224 of the antenna connection conductive member 22 is in thevicinity of the edge portion 222 of the antenna connection conductivemember 22. The opposite side edge vicinity portion 424 is opposed to theedge vicinity portion 224. The electric connection portion 24 belectrically connects the edge vicinity portion 224 of the antennaconnection conductive member 22 to the opposite side edge vicinityportion 424 of the opposite side conductive member 42 through theconnection pattern 44 b (refer to FIG. 9B). Further, also in thisembodiment, wiring means not illustrated connects the two conductivemembers 22 and 24 such that the signal communication may constantly bepossible.

As shown in FIG. 9A, the edge vicinity portion 224 and the opposite sideedge vicinity portion 424 are not connected during communication. Theedge portion 222 and the opposite side edge portion 422 are electricallyconnected by the electric connection portion 24 a. On the other hand, asshown in FIG. 9B, when waiting for the communication (telephone call),the edge vicinity portion 224 and the opposite side edge vicinityportion 424 are connected by the electric connection portion 24 b. Theedge portion 222 and the opposite side edge portion 422 are connected bythe electric connection portion 24 a. Note that the other portions arethe same as those of the first embodiment, and the same numerals aregiven to the same portions and the explanation thereof is omitted.

Next, the operation of the third embodiment is explained.

When the mobile phone unit 1 is waiting for communication (telephonecall) (refer to FIG. 9B), the feed point of the antenna 26 is in thevicinity of the antenna 26. Further, the electrical length of theantenna 26 and the antenna connection conductive member 22 is λ/4.Therefore, the electric current distribution of the antenna 26 and theantenna connection conductive member 22 becomes similar to a λ/2wavelength dipole antenna (center feed type). In other words, theelectric current becomes maximum in the vicinity of the antenna 26 (theelectrical length λ/4). Therefore, when seeing from the antenna 26, again on the opposite side to the LCD side casing 4 (back side) becomeslarge. Further, the electric current becomes minimum in the vicinity ofthe electric connection portion 24 (the electrical length λ/2).

Here, the edge vicinity portion 224 and the opposite side edge vicinityportion 424 are electrically connected by the electric connectionportion 24 b. The edge portion 222 and the opposite side edge portion422 are connected by the electric connection portion 24 a. Therefore,the antenna connection conductive member 22 and the opposite sideconductive member 42 are connected at two positions close to each other.Hence, the antenna connection conductive member 22 and the opposite sideconductive member 42 cause the capacity coupling. Accordingly, theelectric current becomes minimum in the vicinity of the opposite sideedge portion 422 of the opposite side conductive member 42 and becomesmaximum in the vicinity of the receiver 4 a. Therefore, a gain alsobecomes large on the side of the LCD side casing 4 (front side), whenseeing from the antenna 26.

Therefore, almost the same antenna characteristic is shown on the frontside and on the back side when waiting for the communication (telephonecall). Hence, if the radio wave comes (radiates) either from the frontside or from the back side, the reception (transmission) can beperformed favorably, so that it is suitable to wait for thecommunication (telephone call).

On the other hand, the operation when performing the communication usingthe mobile phone unit 1 is similar to that of the first embodiment.

According to the third embodiment, the same effectiveness as the secondembodiment is obtained.

FOURTH EMBODIMENT

In the fourth embodiment, the outer appearance of the mobile phone unit1 according to the first embodiment is changed to be what is called astick type (a type of a single casing).

FIGS. 10A and 10B show a mobile phone unit (mobile communicationterminal) 1 according to the fourth embodiment of the present invention,in which FIG. 10A is a front view and FIG. 10B is a side sectional view.

As shown in FIGS. 10A and 10B, the mobile phone unit 1 includes a casing3. As shown in FIG. 10A, a receiver 4 a, a microphone 4 b, an LCD 4 cand a key button 2 a are provided on the front surface of the casing 3.Further, as shown in FIG. 10B, an opposite side conductive member 42 isdisposed on the front surface side of the casing 3 and a antennaconnection conductive member 22 is disposed on the rear surface side ofthe casing 3. An antenna 27 is connected to the antenna connectionconductive member 22 through the feed point 29. The electrical length ofthe antenna 27 is λ/4. Further, also in this embodiment, the twoconductive members 22, 42 are connected by wiring means not shown suchthat the signal communication can be constantly performed. Note that theother portions are the same as those of the first embodiment, and thesame numerals are given to the same portions and the explanation thereofis omitted.

The operation of the fourth embodiment is almost the same as that of thefirst embodiment.

FIFTH EMBODIMENT

The fifth embodiment is the one in which the circuit boards for packetcommunication are further provided for the fourth embodiment.

FIGS. 11A to 11C show the mobile phone unit (mobile communicationterminal) 1 according to the fifth embodiment of the present invention,in which FIG. 11A is a plan view, FIG. 11B is a front view and FIG. 11Cis a front sectional view. Further, in the front sectional view (FIG.11C), the electric connection portion 24 and the connection pattern 44are not shown.

The circuit boards 82 and 84 are opposed to each other, and thedirection is perpendicular to the direction of the antenna connectionconductive member 22. The circuit boards 82 and 84 are used for thepacket communication, and the circuit board 82 or the circuit board 84is connected to the antenna not shown. Further, the circuit board 82 andthe circuit board 84 are not connected to each other. Furthermore, alsoin this embodiment, the two conductive members 22 and 42 are connectedby wiring means not shown such that the signal communication can beconstantly performed. Note that the other portions are the same as thoseof the first embodiment, and the same numerals are given to the sameportions and the explanation thereof is omitted.

Next, the operation of the fifth embodiment is explained.

The circuit boards 82 and 84 are used for the packet communication. Inthat case, similarly to the case where the antenna connection conductivemember 22 and the opposite side conductive member 42 are not connected,the strength E of a radio wave for the packet communication radiatedfrom the circuit board 82 is almost the same as the strength E of aradio wave for the packet communication radiated from the circuit board84 (refer to FIG. 11A).

Therefore, with respect to the packet communication, almost the sameantenna characteristic is shown on both the sides of the circuit board82 and the circuit board 84. Accordingly, if the radio wave comes (isradiated) from either side, the reception (transmission) can beperformed favorably, which is suitable for the packet communication.

Further, the operation during communication is the same as that in thefirst embodiment.

SIXTH EMBODIMENT

In the sixth embodiment, in a mobile phone unit (mobile communicationterminal) 1 explained in the first embodiment including a key buttonside casing 2, an LCD side casing 4 and a hinge 6, the conduction member22 on the side of the key button side casing 2 and the opposite sideconductive member 42 on the side of the LCD side casing 4 aredifferently connected. FIG. 12 is a front sectional view of the mobilephone unit (mobile communication terminal) according to the sixthembodiment of the present invention.

The key button casing 2 accommodates an antenna connection conductivemember 22, an electric connection portion 24, an antenna 26 and abattery 28.

The antenna connection conductive member 22 is a circuit board on whichvarious electric circuits are mounted. The antenna 26 is connected tothe antenna connection conductive member 22. Further, if the wavelengthof a radio wave that the mobile phone unit 1 uses for the communication(telephone call) is X, the electrical length of the antenna connectionconductive member 22, that is, the electrical length to an edge portion222 from a point where the antenna connection conductive member 22 andthe antenna 26 are connected is λ/4.

The vicinity of the edge portion 222 of the antenna connectionconductive member 22 is electrically connected to the vicinity of anopposite side edge portion 422 of the opposite side conductive member 42through an electric connection portion 24 and a connection pattern 44.However, in this embodiment, the edge portion 222 of the antennaconnection conductive member 22 is not directly connected to theelectric connection portion 24. In other words, as shown in FIG. 12, oneend of a frequency adjusting member 91 made of a chip component or thelike is connected to a connection circuit board (conductive member) 25 bdisposed at a ground potential portion of the edge portion 222 of theantenna connection conductive member 22, and the other end of thefrequency adjusting member 91 is connected to a connection circuit board(conductive member) 25 a. Further, the connection circuit board 25 a isconnected to the electric connection portion 24 and is connected to(made to contact with) the connection pattern 44 from the electricconnection portion 24. As the electric connection portion 24, variousmembers usually used for the electric connection can be used asexplained in the first embodiment; a coil spring, gasket and so on mayalso be used.

The frequency adjusting member 91 may be made of a chip component suchas a coil, capacitor, resistor and so on, or a circuit in which thosechip components are connected in series or in parallel, for example.However, regardless of components, the component having a comparativelysmall value is used in this embodiment. For example, a resistor whoseresistance value is almost zero, or a capacitor whose capacitance valueis 10 PF is used.

Specific examples are shown in FIGS. 13A to 13E, in which as shown inFIG. 13A for example, in the middle of the connection pattern 44 betweenthe antenna connection conductive member 22 and the opposite sideconductive member 42 a coil 91 is connected.

Alternatively, as shown in FIG. 13B, a capacitor 91 b is connected inthe middle of the connection pattern 44 between the antenna connectionconductive member 22 and the opposite side conductive member 42.

Alternatively, as shown in FIG. 13C, a resistor 91 c is connected in themiddle of the connection pattern 44 between the antenna connectionconductive member 22 and the opposite side conductive member 42.

Alternatively, as shown in FIG. 13D, a parallel circuit of a coil 91 dand a capacitor 91 e is connected in the middle of the connectionpattern 44 between the antenna connection conductive member 22 and theopposite side conductive member 42.

Alternatively, as shown in FIG. 13E, a series circuit of a coil 91 f anda capacitor 91 g is connected in the middle of the connection pattern 44between the antenna connection conductive member 22 and the oppositeside conductive member 42.

Alternatively, one chip component or a plurality of chip componentsother than the circuits shown in FIGS. 13A to 13E may be connected.Further, other frequency adjusting member such as an element than thechip components may be used. Note that the other portions are the sameas those of the first embodiment, and the same numerals are given to thesame portions and the explanation thereof is omitted.

According to the configuration of the sixth embodiment as describedabove, the frequency band fw in which the desired antenna characteristic(characteristic of reducing SAR) shown in FIG. 7 explained in the aboveis obtained can be shifted. Specifically, in the case where both circuitboards 22 and 42 are connected by the connection pattern 44 in theconfiguration of, for example, the first embodiment, the frequency bandfw in which the desired front-to-back ratio (F/B) is obtained may be thestate shown in FIG. 14A. At this time, as the configuration of thepresent embodiment, when the frequency adjusting member 91 is connectedto the connection pattern 44, the frequency band fw′ in which thedesired front-to-back ratio (F/B) is obtained shifts as shown in FIG.14B. The frequency shifted can be adjusted in accordance with thecharacteristic of a component constituting the frequency adjustingmember 91.

With being able to adjust the characteristic as described above,adjustment to the frequency band that the mobile phone unit (mobilecommunication terminal) 1 actually uses for the wireless communicationis performed, so that the more desirable characteristic in comparisonwith the case of the first embodiment can be obtained. Further, in thecase that selection of the position where two casings are connected islimited due to the shape of the hinge and so on and the state of thefrequency characteristic set when directly connected at that positionmay not freely selected, the frequency characteristic is minutelyadjusted and the degree of freedom for the design of the casing isimproved.

The operation during communication according to this embodiment is thesame as that of the first embodiment.

SEVENTH EMBODIMENT

The seventh embodiment is the one in which a switch member 92 thatswitches the electric connection using the connection pattern 44 or thelike is further provided, when the frequency adjusting member 91explained in the sixth embodiment is connected to the connection pattern44 through the electric connection portion 24. Specifically, as shown inFIG. 15, the vicinity of the edge portion 222 of the antenna connectionconductive member 22 is electrically connected to the vicinity of theopposite side edge portion 422 of the opposite side conductive portion42 through the electric connection portion 24 and the connection pattern44, however, the edge portion 222 of the antenna connection conductivemember 22 is not directly connected to the electric member 24, accordingto this embodiment.

Specifically, as shown in FIG. 15 for example, one end of the switchmember 92 is connected to a connection circuit board (conductive member)25 b disposed at the ground potential portion of the edge portion 222 ofthe antenna connection conductive member 22 and the other end of theswitch member 92 is connected to one end of the frequency adjustingmember 91 made of the chip components or the like through a connectioncircuit board (conductive member) 25 c, and the other end of thefrequency adjusting member 91 is connected to a connection circuit board(conductive member) 25 a. Further, the connection circuit board 25 a isconnected to the electric connection portion 24, and the electricconnection portion 24 is made to connect to (contact with) theconnection pattern 44.

Various switch means for switching the conduction state such as anelectric switch, a mechanical switch or the like formed of varioussemiconductors and the like can be used as the switch member 92.

A specific connection example is shown in FIG. 16, in which a coil 91 aand a switch 92 a are, for example, connected in the middle of theconnection pattern 44 between the antenna connection conductive member22 and the opposite side conductive member 42.

The switching of the switch 92 a is performed by detecting the change inthe relation of a relative position between the key button side casing 2and the LCD side casing 4, for example. Specifically, with the closedstate, for example, shown in FIG. 1, the connected state is selected andwith the opened state shown in FIG. 2, the not-connected state isselected. Or, vice versa. Further, similarly to the example explained inthe second embodiment, the switching may be performed between the timeof waiting for communication and the time of communication.

Furthermore, when an electric element such as a pin diode is used as theswitch member 92, the electric element may also serve as the frequencyadjusting member 91 by using the value such as resistance value or thelike that the element has in the conductive state. Note that thestructure of other portions is the same as that of the first embodiment,and the same numerals are given to the same portions and the explanationthereof is omitted.

The operation during communication according to this embodiment is thesame as the first embodiment.

1. A mobile communication terminal comprising; an antenna; an antennaconnection conductive member connected to said antenna; an opposite sideconductive member opposed to said antenna connection conductive member;and an electric connection member that electrically connects an edgeportion, which is on the opposite side to said antenna, of said antennaconnection conductive member and an opposite side edge portion, which isopposed to a vicinity of said edge portion, of said opposite sideconductive member.
 2. The mobile communication terminal according toclaim 1, wherein, said electric connection member connects a groundpotential portion of said antenna connection conductive member and aground potential portion of said opposite side conductive member.
 3. Themobile communication terminal according to claim 1, further comprising;a casing which accommodates said opposite side conductive member,wherein said casing includes voice output means which outputs voice onthe opposite side to said antenna connection conductive member when seenfrom said opposite side conductive member.
 4. The mobile communicationterminal according to claim 1, wherein, said electric connection memberperforms (1) no operation of connecting said edge portion and saidopposite side edge portion when waiting for communication, and (2)operation of connecting said edge portion and said opposite side edgeportion during communication.
 5. The mobile communication terminalaccording to claim 1, wherein, said electric connection member performs(1) operation of connecting said edge portion and said opposite sideedge portion and further operation of electrically connecting an edgevicinity portion in the vicinity of said edge portion in said antennaconnection conductive member and an opposite side edge vicinity portion,which is opposed to said edge vicinity portion, of said opposite sideconductive member, when waiting for communication, and (2) operation ofconnecting said edge portion and said opposite side edge portion and nooperation of connecting said edge vicinity portion and said oppositeside edge vicinity portion during communication.
 6. The mobilecommunication terminal according to claim 1, wherein, the totalelectrical length of said antenna connection conductive member and saidopposite side conductive member is half the wavelength of a radio waveused for communication.
 7. The mobile communication terminal accordingto claim 1, wherein, the electrical length of said antenna connectionconductive member and said opposite side conductive member is quarterthe wavelength of a radio wave used for communication.
 8. The mobilecommunication terminal according to claim 1, wherein, a frequencyadjusting member is attached to said electric connection member.
 9. Themobile communication terminal according to claim 8, wherein, saidfrequency adjusting member is formed of at least one of circuitcomponents of a resistor, capacitor and coil.
 10. The mobilecommunication terminal comprising: radio wave radiation means; radiowave radiation connection conductive means connected to said radio waveradiation means; opposite side conductive means opposed to said radiowave radiation connection conductive means; and electric connectionmeans which electrically connects a vicinity of the edge portion, whichis on the opposite side to said radio wave radiation means, of saidradio wave radiation connective conductive means and a vicinity of theopposite side edge portion, which is opposed to said vicinity of theedge portion, of said opposite side conductive member.